Directional drilling is a useful technique for several procedures such as utility installation, etc. One common type of directional drilling is horizontal directional drilling (HDD), where a drill stem is extended essentially horizontally to form passages underground without the need for a trench. Drill heads in directional drilling typically have a feature which causes the drill head to steer in one direction when forced ahead by a drilling device. During a boring operation, pressure is applied through a drill stem from behind to the drill head. During a straight bore, the drill stem is typically rotated at a regular rate so that on average, only straight ahead drilling is accomplished. In order to steer a drill head, the rotation is temporarily stopped, and the drill head is allowed to steer in the desired direction. Once the steering maneuver is complete, the drill head is again rotated at a regular rate for straight ahead drilling.
In many HDD operations, an electronic transmitter called a sonde is coupled to a distal end of the drill stem. Signals transmitted from the sonde are detected by a receiver carried by an operator above ground. Various characteristics of the detected signal are then used to indicate a location and orientation of the distal end of the drill stem. This information can then be used to steer the drill stem in a desired direction.
When a bore is completed, typically the sonde and associated sonde housing are removed and a pipe, cable, transmission line. etc. is coupled to the drill stem to be pulled into the bore as the drill stem is pulled back. A common attachment between components such as the sonde housing and the drill stem is a threaded connection such as a tapered thread as known in the industry. Currently large pipe wrenches are sometimes used to loosen the threaded connection at the sonde housing, however use of large pipe wrenches within an exit pit of a horizontal bore presents a level of safety risk. Large torque forces can be necessary to loosen the threaded joint which can make breaking the connection difficult. Additionally, sonde housings and drill heads are expensive to manufacture. Because multiple configurations of drill heads are typically needed to address varying soil conditions, there is an ongoing need in the field to reduce costs for the collection of drill equipment needed. What is needed is an improved drill system and method that makes connection and disconnection of drill stem components easier, improves safety, reduces cost, etc.